Originally introduced in the mid-’70s, the
Model 402 Aphex Aural Exciter was an instant
hit—but you couldn’t buy one. The few
units that were built could only be rented at
considerable expense. The seminal tube-powered
processor, which added musically related
harmonics to audio signals, was used on select
studio sessions for such icons as Paul McCartney,
Fleetwood Mac, James Taylor, Jackson
Browne and Linda Ronstadt. Its ability to add
and enhance detail and presence on both individual
tracks and complete mixes earned the
august processor a devoted following. Aphex
subsequently produced low-cost, solid-state
versions of the Aural Exciter for retail sale, but
the original tube-based units were lost in the
mists of time. Or so we thought.

More than 30 years later, Waves obtained
the original hardware unit from Aphex’s storage
and modeled its distinctive sonic character
with the guidance of producer/engineer
Val Garay, a high-profile Exciter user back in
the day.

The cross-platform Waves plug-in is available
singly in both TDM (TDM, RTAS, Audio
Suite, AU and VST) and Native (all the foregoing
formats except TDM) versions. It’s also
included in the Waves Mercury bundle. Mono
and stereo configurations and resolution up to
24-bit/192kHz render the Aphex Vintage Aural
Exciter ready for both mixing and mastering
duties. I tested the AU version of the plug-in in
MOTU Digital Performer 7.2.1 using an 8-core
Mac Pro running Mac OS 10.5.8.

EXCITEMENT A LA MODE
Due to its phase-related idiosyncrasies, the
original Model 402 produced different sounds
when used on a mixer’s channel insert (MIX
mode) vs. in an aux send/return path (AX
mode, which was Garay’s modus operandi).
Waves modeled both sets of sonic characteristics
and assigned them to two respective
modes for the plug-in, dubbed MIX2 and AX.
The company anticipated that DAW users
would also want the convenience of generating
the AX mode’s response when the plug-in is
used on a track’s insert, so the company created
an additional mode for the plug-in, tagged
MIX1, which does just that.

The upshot is that you should use either
MIX1 or MIX2 mode—both of which blend
generated harmonics with the dry signal—
when the plug-in is instantiated on an individual
track’s insert; you adjust the GUI’s AX
MIX control to set how much Exciter effect you
want to add to the dry signal. MIX2 mode audibly
changes the frequency response of the
signal, especially when high AX MIX control
settings are used, so it’s most useful for coloring
individual tracks. The more spectrally balanced
MIX1 mode is suited to either mixing
or mastering.

AX mode kills all dry sound at the plugin’s
output, leaving only the Exciter effect. Use
AX mode when the plug-in is placed on an aux
to which you’ve bused your dry track. The AX
MIX control is disabled in AX mode, so adjust
the level of excitation using the dry track’s bus
send. A fourth mode, BP, models the original
hardware’s BP (bypass) mode, which was not a
pure bypass and sounds slightly colored.

No matter which of the three active modes
you use, the sound of the plug-in changes as
you drive it harder. A wide-ranging input level
control provides up to 18 dB of boost or attenuation
to achieve the desired sound and manage
headroom. The output level control, likewise,
has a +/-18dB range. A VU meter (two meters
for stereo configuration) shows either input,
output or AX (harmonics) levels—selectable
via a rotary switch—and sports a clip LED calibrated
to 0 dBFS. You can recalibrate the meter’s
headroom, which is 18 dB by default.
Waves also modeled the 402’s analog
noise. You can adjust the noise level of the
plug-in from -48 to 0 dB (0 dB is commensurate
with the original hardware’s noise level),
or turn the noise off . You can also add 50- or
60Hz hum, modeled on the hardware unit’s
power supply, or disable hum altogether. A and
B workspaces are provided to help compare different
setups.

TAKING FLIGHT
Once I learned how best to use the Aphex Vintage Aural Exciter’s different modes, the
rest was easy. The plug-in’s frugal control set
made it child’s play to get great sounds.
Aural Exciter sounded awesome on male
lead vocals, lending increased clarity and intelligibility.
MIX1 mode sounded the warmest
and most balanced. With moderate AX MIX
settings, it brought the midrange slightly forward
but also increased sibilance somewhat.
MIX2 mode, on the other hand, virtually
eliminated all sibilance while pulling the
midrange dramatically forward—perfect for
rock vocals.

MIX1 with high AX MIX settings tightened
up fl abby electric-bass guitar notes
beautifully, making the instrument sing.
However, I wasn’t charmed by what the plugin
did to acoustic guitar: MIX1 sounded too
tinselly and MIX2 too nasal. On kick drum,
the plug-in made the beater slaps sound harsh
and cutting. But Aural Exciter sounded outstanding
on snare drum, as both MIX1 and
MIX2 modes made it sound like a bottom mic
had been added to this top-miked track, with
MIX1 simultaneously producing warmth and
sizzle and MIX2 mode bringing a bright and
slappy tone. One caveat: If there is heavy hi-hat
spill on your snare track, high AX MIX
settings will make your ears bleed.

Next, I bused a finished mix to an aux and
instantiated Aural Exciter in AX mode on the
aux’s insert. This setup let me temper how
hard I drove the plug-in’s input (using the bus
send) without reducing the dry mix’s level.
With a moderate amount of aural excitement
applied to the mix, the plug-in enhanced detail
and lent an open, airy quality. The downside
was that some elements of the mix,
such as arpeggiated acoustic guitar, sounded
slightly glassy. I got similar results by placing
the plug-in on the master channel’s insert and
using MIX1 mode with the AX MIX control
set to around 5 (turned up halfway). Injudiciously
goosing the AX MIX control a lot higher
produced a cutting, almost transistorized
sound, cautioning moderation. I appreciated
that I could adjust the meters’ headroom to 8
dB for mastering (while using MIX1 mode)
because the default calibration otherwise kept
the meters almost constantly pinned during
loud choruses.

With the plug-in still sitting on the master
channel’s insert, I auditioned AX mode
just for grins (killing all dry sound). I was
instantly enamored by how it evoked a bandlimited,
slightly distorted sound reminiscent
of a poorly tuned radio, albeit with enhanced
high frequencies. Serendipity!

HARMONICS REDUX
I got my best results using the Waves Vintage
Aural Exciter on individual tracks. The
plug-in sounds awesome on select lead vocals,
snare drum and electric bass. But with judicious
use, it can also transform a cloudy mix
into an open canvas. This reasonably priced
plug-in would make a great addition to any engineer’s
toolkit.